USRE27244E

USRE27244E - Device for building up high pulse liquid pressures

Info

Publication number: USRE27244E
Authority: US
Priority date: 1969-11-26
Filing date: 1969-11-26
Publication date: 1971-12-14

Abstract

A DEVICE FOR BUILDING UP LIQUID PRESSURE PULSES COMPRISES A CYLINDER HOUSING A PISTON, AND AT ONE SIDE OF THE PISTON, THE CYLINDER''S FACE IS FILLED WITH COMPRESSED GAS AND SERVES AS A LOW PRESSURE CHAMBER DESIGNED TO ACCUMULATE ENERGY FROM A FORCED STROKE OF THE PISTON IN THE DIRECTION OF THE CHAMBER. THE SPACE AT THE OTHER SIDE OF THE PISTON IS FILLED WITH LIQUID AND SERVES AS A HIGH PRESSURE

CHAMBER. HIGH PRESSURE IN THE CHAMBER IS BUILT UP AS A RESULT OF INPACT OF THE PISTON ON THE LIQUID IN THIS CHAMBER UPON RECIPROCATION OF THE PISTON IN THE CYLINDER, THE PISTON OBTAINING KINETIC ENERGY IN THE COURSE OF ACCELERATION DURING EXPANSION OF THE COMPRESSED GAS.

Description

Dec. 14, 197] 5, v, vorrsg ovs y EI'AL Re. 27,244

DEVICE FOR BUILDING UP HIGH PULSE LIQUID PRESSURES Original Filed May 5, 1965 v 5 Sheets-Sheet 2.

1971 a. v. VOITSEKHOVSKY ETI'AL Re. 27,244

DEVICE FOR BUILDING UP man PULSE mourn PREssuREs Original Filed May 5. 1965 5 Sheets-Sheet I Dec. 14, 197] v, VOITSEKHOVSKY EI'AL Re. 27,244

DEVICE FOR BUILDING UP HIGH PULSE LIQUID PRESSURES Original Filed May 5, 1965 5 Sheets-Sheet I Dec. 14, 197] 9, v. Vdrrsgmqdvs Y ETAL Re. 27,244

DEVICE FOR BuILbING UP HIGH PULSE LIQUID PRESSURES Original Filed May 5 les s Shets-Sheet 4 FIGS &

1971 B. v. VOITSEKHOVSKY ETA!- 27,244

DEVICE FOR BUILDING UP HIGH PULSE LIQUID PRESSURE-S Original Filed May 5. 1965 5 Sheets-Sheet 5 J: 1111: w 0 j United States Patent Oflice Re. 27,244 Reissued Dec. 14, 1971 27,244 DEVICE FOR BUILDING UP HIGH PULSE LIQUID PRESSURES Bogdan Vjacheslavovich Voitsekhovsky, Elmar Andreevich Antonov, Valentin Pavlovich Nickolaev, Grigory Yankelevich Shoikhet, Vladimir Mikhailovich Dudin, Alexandr Vasiljevich Shevchenko, and Nickolai Fedorovich Olenkov, Novosibirsk, U.S.S.R., assignors to Institute Gidrodinamiki Sibirskogo Otdelenia Akademi lflauk U.S.S.R., Novosibirsk, U.S.S.R.

Original No. 3,412,554, dated Nov. 26, 1968, Ser. No. 453,424, May 5, 1965. Application for reissue Nov. 26, 1969, Ser. No. 888,174.

Int. Cl. F15b 7/00 U.S. Cl. 60--54.5 HA 36 Claims Matter enclosed in heavy brackets II] appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue.

ABSTRACT OF THE DISCLOSURE A device for building up liquid pressure pulses comprises a cylinder housing a piston, and at one side of the piston, the cylinders face is filled with compressed gas and serves as a low pressure chamber designed to accumulate energy from a forced stroke of the piston in the direction of the chamber. The space at the other side of the piston is filled with liquid and serves as a high pressure chamber. High pressure in the chamber is built up as a result of inpact of the piston n the liquid in this chamber upon reciprocation of the piston in the cylinder, the piston obtaining kinetic energy in the course of acceleration during expansion of the compressed gas.

The present invention relates to devices for building up static and dynamic liquid pressures of relatively high magnitudes and of pulse form and a method of employing such devices.

Pressure magnitude is generally limited only by the strength of the material of the vessel in which this pressure is built up.

Known devices for building up liquid pressures include those based on the use of an electric discharge or of a detonation of an explosive directly in the liquid. The practical use of such known devices is limit-ed by the low efficiency of the utilization of the liberated energy.

Devices, which use an electric discharge in liquid to obtain pulse pressures, require high-voltage equipment. This equipment is rather complicated in operation especially under industrial conditions. Besides, high-voltage equipment is very expensive and does not have a high degree of reliability.

Devices, which use the energy of explosions in liquid for building up pulse pressures, also have a number of disadvantages. Thesedisadvantages include the danger of employing explosives under industrial conditions, mechanical difiiculties and automatization difiiculties, as well as the high cost per unit of energy liberated by an explosive.

An object of the present invention is to eliminate the disadvantages of these known devices.

A particular object of the invention is to provide an improved industrial installation for building up liquid pressure pulses, said installation having a higher eificiency than known devices.

These objects are achieved, in accordance with the invention, by using a device for building up liquid pressure pulses, with at least one cylinder, said cylinder housing a piston. At one side of the piston, the cylinder space is filled with compressed gas and serves as a low-pressure chamber designed to accumulate energy from the forced stroke of the piston in the direction of the chamber. The space at the other side of the piston is filled with liquid and serves as a high-pressure chamber. High pressure in the chamber is built up as a result of an impact of the piston upon the liquid in this chamber, said piston obtaining mechanical energ in the process of its acceleration during expansion of compressed gas.

The device is fitted with one or more receivers for compressed gas, said receivers communicating with the lowpressure chamber through openings in the cylinder side wall, said openings being located close to the face wall of the low-pressure chamber.

Other objects and features of the inventiomare next described with reference to an exemplary embodiment as illustrated in the appended drawings wherein:

FIG. 1 is a sectional view of a device, provided in accordance with the invention wherein the forced travel of the piston for compressing gas is effected by liquid pressure, the device including a high-pressure chamber housed in a cylinder body;

FIG. 2 is a sectional view of a modification of the device in which the forced travel of the piston for compressing gas is eifected mechanically;

FIG. 3 is a sectional view of a modification of the device in which the high-pressure chamber is mounted in the piston body, the piston being moved by liquid pressure;

FIG. 4 is a sectional view of a part of the device employing a floating piston placed in the high-pressure chamber;

FIG. 5 shows a further embodiment and is a partially sectional view of a device which incorporates a jet head and a mechanism for operating the jet head;

FIG. 6 is a partial sectional view of another device and a mechanism for opening and closing the opening in the jet head in accordance with another embodiment;

FIG. 7 is a general view of a device of the invention with a connected vessel in section;

FIG. 8 is a general view of a device of the invention with a closed vessel connected to it, in section, with a die and a blank positioned in said vessel;

FIGS. 9 and 10 show the device with the connected vessel housing a piston; and

FIG. 11 shows the device being used as a press with the die and the device being movably installed.

The device as shown in FIG. 1 consists of a hollow rigid member such as a closed end cylinder 1 whose closed end bore serves as a low pressure chamber 2. The low pressure chamber houses a solid reciprocating piston 3 which defines a space 2a or gas receiving chamber to the right as seen in FIG. 1 and a liquid receiving chamber 2b to the left of the piston 3 as seen in FIG. 1. Cylinder head means 4 to 4" [4], housing a cylindrical high pressure chamber 5, is rigidly fixed by a thread to the front part of cylinder 1 and is coaxial with the latter. Cylinder head means 4 to 4" [4] has prestressed walls. The high pressure chamber 5 ends with an outlet opening 6. The high pressure chamber may have several outlet openings depending upon the requirements of the proposed device. The crosssectz'onal area [section] of opening 6 may correspond to the internal cross section of chamber 5 of cylinder head means 4 to 4 [4]. High pressure chamber 5 of cylinder [=4] head means 4 to 4" is periodically filled with liquid.

The front part of cylinder head means [4'] 4 to 4" is provided either with an internal or external thread 7 by which loads such as for instance, a hydropress cylinder are connected to high pressure chamber 5. In the rear part of cylinder [5] head means [4] 4 to 4" its chamber 5 has taper shaped widening 8 best described as a tapered countersink mouth portion which serves as a guide for an impact piston or rod 9 which is, as shown, a coaxial cylindrical forward extension of piston 3. It should be oted that high pressure chamber may have a cross secon corresponding to the cross section of piston 3, so that 1e rod need not be employed.

The length of taper shaped widening 8 is limited by hannels disposed in the side wall of cylinder head team 4 to 4" [4], channels 10 extending in a known tanner from the bottom end of the countersink portion 8 djacent the transition area where said countersink poron joins the cylindrical surface of high pressure chamber ommunicating [with] between liquid receiving [low ressure] chamber 2b [2] and high pressure chamber 5. hese channels are intended for free escape of liquid hen rod 9 of piston 3 passes said widening 8. The total ross section of channels 10 is chosen at the maximum llowed by the design.

Channels 10 may not be necessary, if a floating piston 1 is used in high pressure chamber 5 (see FIG. 4). In 1is case, there should be a [guaranteed] clearance beveen the internal wallof cylinder head means [4] 4 7 4" and rod 9 of piston 3, as well as a limiting shoulder 2 serving to preclude dopping of piston 11 out of chamer 5.

Return of piston 11 into the initial position after the npact is provided by the delivery of a liquod of increased npact is provided by the delivery of a liquid of increased ito chamber 2b [2] of cylinder 1.

The part of the wall of cylinder 1 which contacts ylinder head means [4], 4 to 4" has one or more inlet leans or openings 13 which serve to deliver liquid under ressure into chamber 2b for forced travel of piston 3. he through section of openings 13 is determined by the elocity of return of the piston 3 to the extreme rear osition. Openings 13 also serve for filling of high-presire chamber 5 with liquid.

The wall of cylinder 1 has, spaced at the side of cyliner head means 4 to 4" [4], outlet means or openings 14, lrough which openings the liquid in front of the piston 1 chamber 2 is discharged during piston acceleration. It desirable that the total cross section of openings 14 be ot less than the internal cross-sectional area of cylinder Openings 14 are periodically closed by a hollow cylinrical valve means or slide 15 in the form of a cylindrical ushing on cylinder 1.

At one side, the travel of slide 15 is limited by a stop 6 located on the external surface of cylinder 1 and, from 1e other side by packing collar 17, which has a gasket of aft material (for instance, red copper). Pointed nose 18 it slide 15 rests upon said gasket. Such embodiment proides fortight closing [overlapping] of openings 14.

At its rear, low-pressure chamber 2a communicates 'ith gas containing means or receivers 19 through openigs or ports 20 in the side wall of cylinder 1 and also ia annular air collector 21, said collector being rigidly xed to receivers 19 and being in tight contact with the xternal surface of cylinder 1. A slight longitudinal moverent is possible between the collector and cylinder.

Such connection of cylinder 1 with receivers 19 serves relieve cylinder 1 of inertia loads of the weight of the aceivers 19 at the moment of piston impact upon the quid. Between cylinder 1 and air collector 21 there is a acking 22. At their fronts, receivers 19 are fixed to a washer 24 by rods 23, said washer being located at the 7011i; part of cylinder [4] head means 4 to 4" and preluded by lug 25 from possible movement. Receivers 19 re disposed along a circle in parallel to the axis of ylinder 1. The number of receivers is optional.

The cross section of openings 20 should be maximum; aid openings are disposed in a common lateral plane. The istance between openings 20 and face [or] of wall 26 f chamber 2a of cylinder 1 is determined by the time of Lg of piston 3 in its rear position. Bore end, cylinder ead means or wall 26 is connected with cylinder 1 by ap nut 27. Placed between the face of cylinder 1 and 'all 26 is packing 28 which provides for the fluid tightess of chamber [2] 2a.

As well illustrated in FIG. 1 there is a threaded opening 29 in wall or cylinder head means 26, with a liquid venting command [control] valve means 30 fixed therein and fitted with a pin 31 extending into chamber 2a of cylinder 1 from a valve member 31, slidably mounted withinthe body of valve means 30. Valve member 31 occupies a large portion of the space 47 within. the valve means 30 and controls communication between the space 47 and the surrounding atmosphere by opening and closing passageway 47 leading from space 47 to the outer air.

Pn 31 is sealed in its opening by a sleeve 32. Command [Control] valve means 30 is connected via

main line

33 and 34 with liquid receiving [low-pressure] chamber 2b [2] and right-hand space 35 of jack 36 respectively (a second jack is not shown). Pistons 37 of jacks 36 are rigidly coupled with slide 15 through rods 38. Left-hand spaces 39 of jacks 36 are coupled with receivers 19 through main line 40.

With the valve means 30 as described it is to be realized that pressurized liquid from main line 33 can pass through the interior space 47 and into main line 34 under full pressure without moving the valve member 31'. However when impact of the piston 3 on the end of pin 31 opens the valve member 3] liquid flow from the right hand space 35 of jack 36 through the valve means 30 and out through the passageways 47 will hold the valve member 31' in the open. position until flow from the main. line 34 through the valve means 30 ceases when the piston 37 of the jack 35 reaches end of travel to the right as seen in FIG. 1. With the stopping of liquid flow from the main line 34 through the valve means 30 the valve member 31' closes and remains closed under all conditions of pressure and liquid flow until the pin 31 is again impacted by the piston 3.

The rear part of piston 3 is provided with an angular channel 41 in which a non-return valve 42 with axial opening 43 is secured. Valve 42 is designed for the bypass of compressed gas from the space behind the piston in chamber [2] 2a into receivers 19, when piston 3 passes opening 20 while moving [in] into its rear position and flow rate controlled gas flow from receivers 19 into chamber 2a when the piston 3 is moving away from wall 26.

The front part of rod 9 of piston 3 ends in tapershaped lug 44, which serves as a hydraulic brake to damp the remaining energy of the piston. Piston 3 is fitted with packings 45 intended to preclude leakage of liquid and gas. Rod 9 throughout its lengths is provided with lateral circular grooves 46 which serve as labyrinth packings for the high-pressure liquid at the time of the impact.

The external surface of rod 9 is coated with an antifriction material. Rod 9 can be integral with piston 3, as shown in FIG. 1, or can be rigidly fixed to the body of the piston.

The proposed device operates according to the following procedure.

At the end of the working stroke, when piston 3 is in the extreme front position (to the left in FIG. 1), receivers 19 and the space of chamber 2a [2.] behind the piston are filled with gas compressed up to 50100 kg./sq. cm. or atmospheres of pressure approximately.

It should be noted that, in this case, the compressed gas is not consumed in the process of operation, while the losses caused by leakage, due to improper sealing, should be periodically replenished.

Piston 3 separates [the front part of] chamber 2b [2], as shown in FIG. 1, from discharge openings 14, which are opened at the moment.

Through openings 13, the liquid being pumped under pressure up to kg./sq. cm. (the pump is not shown in the drawings) is delivered into said front part of chamber 2b [2], affects the front face of piston 3 and moves, at the same time, along main line 33 through spaces 47 in the casing of valve means 30 (which is closed) and main line 34 and is delivered into right-hand space 35 of jacks 36. When the pressure of liquid in said front part;

of chamber 2b and in spaces 35 of jacks 36 reaches a certain value, slide coupled to jacks 36 closes discharge openings 14, and at this moment piston 3 starts to move to the extreme rear position and chamber 5 is filled With liquid.

With movement of piston 3 compressed gas from cham ber 2a is delivered into receivers 19 through openings 20 and air collector 21. When piston 3 overlaps opening 20, compressed gas remaining in [the rear part of] chamber 2a [2] [behind piston 3] is bypassed into receivers 19 through non-return valve 42 and channel 41.

When in its extreme rear position, piston 3 affects pin 31 of valve means 30. In this case, valve member 31 opens and though the piston separates from pin 31, said valve member 31' stays opened until complete discharge of liquid from space 35 of jacks 36. Under the influence of compressed gas, supplied from receivers 19 along main line into space 39 of jacks 36, slide 15 opens discharge oepnings 14, which is accompanied by drop of pressure in chamber 2b [2] of cylinder 1 in front of piston 3. From this moment on, piston 3 is affected only by the pressure of the compressed gas, delivered from receivers 19 through channel 41 and opening 43 of valve 42, said valve 42 staying closed.

Acceleration of piston 3 begins after openings 20 are no longer closed. The distance between wall 26 and openings 20 is covered by piston 3 at a low speed depending upon the cross-section of opening 43. The value of the cross-section of opening 43 is determined by the time of opening of openings 14 by slide 15 so that the time required for the mean face of [slide] piston to cover the distance between inner face of wall 26 and openings 20 exceeds the time necessary for opening of openings 14.

At the moment of acceleration of piston 3, slide 15 should completely open openings 14, while valve means 30 should become closed.

During acceleration, the energy accumulated by compressed gas in the process of compression changes into kinetic energy of piston 3, while the liquid which was in front of the piston in chamber 2b [2], is discharged through openings 14, by the end of acceleration, rod 9 of piston 3 enters chamber 5 through taper-shaped widening 8. After rod 9 passes channels 10, an impact of piston 3 upon the liquid in chamber 5 takes place, which results in a sharp pressure increase. The liquid which receives the energy during the impact is discharged through opening [ings]6. The remaining kinetic energy of piston 3 is clamped by hydraulic brake 44.

Thus with such structure, when the front face of piston 3 passes the outlet ports 14 the face of piston 3 moves into the last portion of chamber 2b and reverses the flow of liquid through inlet means 13 because of liquid being displaced by piston 3. This reverse flow of liquid acts through main line 33, the space 47 of the valve means 30 and main line 34 helping to actuate jacks 36 and close valve 15 in readiness for the next cycle of operation.

It should be noted that hydraulic brake 44 may be disposed in the rear part of high-pressure chamber 5. The cross section of chamber 5 may correspond tothe cross section of chamber 2, or in other words to the cross section of piston 3.

Described below is another embodiment of the proposed device and its operating principle.

The device shown in FIG. 2 consists of cylinder 1', to whose rear part power cylinder 48 is attached coaxially. Piston 3 housed in cylinder 1, dividing the same into two spaces 11] and 2'.

Fixed rigidly to the front part of cylinder 1' With the help of a threaded connection, is cylinder [4] head means 4, whose chamber 5' serves as a high-pressure chamber with prestressed walls. The side wall of cylinder [4] head means 4' is provided with a channel 49, in which non-return valve 50 is located. Channel 49 serves to deliver liquid into chamber 5' [5].

Taper-shaped widening 8 and channels 10, though not shown in the drawing, are in this case obligatory.

The front part of cylinder head means 4' is provided with thread [7] 7, which serves for the same purpose as in the above mentioned cases, and with opening [6] 6'.

Besides, in the side wall of cyinder [4] head means 4 adjoining high-pressure chamber [5] 5, channels 51 are provided for the discharge of air during the working stroke of the piston. Rod [9] 9' of piston [3] 3 ends in taper-shaped lug [44] 44' and has circular grooves [46] 46.

Piston [3] 3 has space 52 in its rear part, which is entered by latching means or catching device 53 fitted with hollow rod 54. Rod 54 of device 53 passes through axial opening 55 in the rear face wall [26] 26' of cylinder [1] l and is rigidly fixed to piston 56 of power cylinder 48.

The front part of rod 54 has widening 57. Installed in the body of widening 57 are at least two cams 58, which can move in the radial direction. In its body, rod 54 has channel 59, which communicates through opening 60 and channels 61 in the body of piston 56 with space 62 of power cylinder 48. The internal wall of space 52 is in the body of piston [3] 3 is provided with annular slot 63, which is entered by earns 58.

The rear part of piston [3] 3 is provided with channels 64, which communicate with space 52 or circular groove 65 at the external surface of widening 57; circular groove 65 at certain moments communicates with annular slot 63. The body of widening 57 has longitidinal through channel 66 which serves to discharge compressed gas from space 52 of piston [31 3, when Widening 57 enters said space. Centering of catching device 53 in chamber [2] 2' of cylinder [1] 1' is effected with the help of stops 67 with which the body of widening 57 is equipped.

Chamber [2] 2 of cylinder [1] I communicates with receivers [19] 19' through openings [20] 20 in the side wall of cylinder. The cross-section of openings [20] 20 in this case also should be selected so as to be maximum; said openings are to be disposed in a common lateral plane.

Wall [26] 26 of cylinder [1] 1' houses non-return valve 68 used for the discharge of compressed gas into receivers [19] 19' in order to move piston [3] 3 into the rear position, and valve 69 which is opened by piston [3'] 3', when the latter is in its extreme rear position.

The purpose of valve 69 is to discharge compressed gas from the space behind the piston into command control valve [30] 30' disposed on the. external surface of cylinder [1] 1'.

Located in the side wall of the front part of power cylinder 48 are channels 70 for the escape of discharged liquid, said liquid being supplied into spaces 62 of power cylinder 48 along channels 71 in order to move piston 56.

Channels 70 and 71 communicate with circular chambers 72 and 73 respectively, said chambers being separated by wall 74. Chamber 72 is opened to the atmosphere through opening 75, which is periodically overlapped by control valve 76. Chamber 73 is connected with the pump not shown in the drawings, through channel 77, and with main line 78 and opening 79' in its side wall is connected to control valve 76 and command valve [30] 30'.

The rear wall of power cylinder 48 has one or more openings 80, through which openings space [62] 62' con stantly communicates with receivers 81 of low-pressure gas. The pressure of gas in receivers 81 should be approximately up to 7-10 kg./sq. cm. The numbers [numbers] of receivers 81 is optional. It should be noted that the volume of any receivers should be chosen so that with the expansion of gas, the drop of pressure in these receivers does not exceed 2030 percent. High-pressure receivers [19] 19 in this case are attached to the external side of cylinder [1] 1' with antifriction bearings 82.

The operating principle of the device as described with :ference to the present embodiment is as follows:

Prior to operation, receivers [19] 19 are filled up with Jmpressed gas under a pressure of 50-100 kg./ sq. cm., 'hile receivers 81 are filled up with compressed gas with re pressure ranging from 7 to kg./sq. cm. The liquid supplied into the front part of space 62 of power cyliner 48 through channel 77, circular chamber 73- and hannel 71. Further on, through channels 61 in the body E piston 56 openings 60, channels 121 and channel 59, 1e liquid is delivered to cams 58 and separates them.

Being separated, the cams enter annular slot 63. At 1e same moment, the liquid from chamber 73 through pening 79' and main lines 78 and 83 is admitted into JI1tIOl valve 76, which, being shifted, closes opening 75 E circular chamber 72, command valve [30] 30' being t this moment closed.

The liquid, supplied into the front part of space 62, ifects piston 56 and piston [3] 3 connected with the itter, thus moving piston 56 to the extreme rear posion. In this case the low-pressure compressed gas from Jace [62] 62' behind piston 56 flows into receivers 81, 'hile the compressed gas from chamber [2] 2' behind iston [3] 3 gets into receivers [19] 19' through open- 1g [20] 20' and air collector [21] 21 When piston [3] 3 closes openings [20'] 20' in the side all of cylinder [1] 1', the compressed gas, which reiains between wall :[26] 26' and piston [3] 3', flows ito receivers [19] 19 through non-return valve 68 and rain line 84.

When in the extreme rear position, piston [3] 3' affects alve 69, opening the latter, and discharges the remaining ompressed gas which is delivered into command valve 30] 30 through main line 85.

Being affected by the compressed gas, command valve 30] 30' opens, reducing the liquid pressure in control alve 76, and valve 68 at this moment closes. With pis- )n [3] 3 moving backwards, valve 69 also closes.

After the drop of the liquid pressure in control valve 6, the compressed gas which is admitted from receivers 19] 19' through main line 86 to control valve 76, opens 1e latter, thus reducing the liquid pressure in space 62.

From this moment on, piston [3] 3 and piston 56 can 'avel only under the action of the compressed gas suplied from receivers 81 into the [rear part of] space 62] 62'.

In this case the leakage of compressed gas from reeivers through opening [20] 19' in cylinder [1] 1 into 1e space formed by the displacement to the left of pisms [3] 3' and 56 (as shown in the drawing) is limited y special packings between piston [3] 3' and wall [2'6] 6 (not shown in the drawing).

The ratio between the rate of displacement of pistons 3] 3' and 56, on their way from the time they leave all [26] 26' until openings [20] 20 open, the aboveientioned leakage should be such that a vacuum is reated in the space formed behind piston [3] 3' and ams 58 lose their contact with piston [3] 3 The air leaves the space in front of piston [3] 3' via hannels 51. Coinciding in time with a drop in the liquid ressure in space 62, there occurs a drop in the pressure f liquid in channel 59 of rod 54-, said liquid moving no the front part of space 62.

Cams 58 leave annular slot 63 of piston [3] 3', being ifected by the compressed gas supplied from receivers 19] 19' through channels 64 and groove 65.

As soon as piston [3] 3' opens openings 20, it becomes isengaged from catching device 53, which continues roving forward at a low speed under the effect of the ompressed gas delivered from receivers 81, while piston 13] 3 is accelerated by the compressed gas supplied Tom receivers [19] 19 through openings [20] 20.

By the moment rod [9] 9' of piston [3] 3 enters hamber [5] 5, the latter should be necessarily filled p with the liquid delivered from the pump through channel 49 and non-return valve 50. The impact of the piston with the liquid results in discharge of said liquid through opening [6] 6'.

At the extreme front position of piston [3] 3', lug [44] 44 on rod [9] 9 enters opening [6] 6, thus eliminating the impact of the piston with the walls of chamber [5] 5. Catching device 53 continues moving forward under the effect of the compressed gas supplied from receivers 81. When being in the extreme position, catching device 53 enters space 52. of piston [3] 3, while piston 56 rests upon wall [26] 26 of cylinder [1] 1. Further on the process is repeated.

The device shown in FIG. 3 differs from the first two embodiments in location of the high-pressure chamber. High-pressure chamber [5] 5" is made in the body of piston [3] 3"; the front face wall of cylinder [1] 1" has internal lug 87 whose cross section corresponds to the cross section of chamber [5] 5". In this case the space of piston [21'] 3" serving as a high-pressure chamber is provided with taper-shaped widening [8'] 8" and channels [10 10", said widening and channels being used for the same purpose as in the above-mentioned cases. The external surface of lug 87 has circular grooves [46] 46"; axial opening [6] 6" is made in the body of said lug. Besides the diiferences mentioned, the device in this embodiment does not vary in principles from the devices described above.

Piston [3] 3" is set in the initial position, as shown in FIG. 3, through the use of the liquid pressure, but also with the help of a power mechanism.

In this embodiment, the maximum value of the pressure of discharged liquid is less than in the first two embodiments, and depends upon the strength of the wall of highpressure chamber ,[5] 5", the size of these walls being in this case limited by the design. In this case, the device has smaller weight and overall dimensions. Chamber [5] 5" is filled up with liquid automatically with piston [3] 3" being set in the initial position.

Described hereinafter are possible cases of the utilization of the proposed device. FIGS. 5 and 6 illustrate the case when the proposed device is employed for obtaining pulse dynamic sprays. Screwed to the front part of cylinder head means 4 is jet head 88, which has axial opening 89 coinciding with outlet opening 6 of high-pressure chamber 5.

In case, piston 3 is set in the initial position by the pressure of liquid, it is expedient to equip the device with mechanism 90 serving to periodically open and close opening 89.

Mechanism 90 can be made as slide 91, driven by hydraulic cylinder 92 and pneumatic cylinder 93 (FIGS. 1 and 5), said cylinders being respectively connected through a main line with the right-hand space of jacks 36 and receivers 19 so, that mechanism 90 and slide 15 operate in synchronism (connections not shown in FIG. 1). It is quite possible, that [slide 91] cover 9] may be driven by a system of levers 94 (FIG. 6) coupled with slide 15, [as is] shown in FIG. [6] 1. In an embodiment employing the catching device (see FIG. 2) opening 89 may not be overlapped. It is desirable to make opening 89 wider at the outlet in order to make the spray free from the remnant acoustic waves and to provide for its long range.

The described device can be used, for instance, to crush rocks of average strength, to clean castings of sand and scorching, to knock out rods in castings, to clean cement furnaces without their stopping, and for other similar purposes. The device can be used to punch holes in lamination material placed on a die.

As shown in FIG. 7, the device can be used as a highpressure pump. In this case the sprays are discharged through non-return valve 95, for instance into vessels 96 to be tested for the strength of the walls. The advantage of the device when used as a high-pressure pump is the absence of packings on rod 9 of piston 3. The

absence of packings is explained by the high speed of movement of piston 3 in cylinder 1. Circular grooves 46 provide for minimum leakage of liquid through the clearance between rod 9 of piston 3 and the internal wall of high-pressure chamber 5.

One more example of employment of the described device is illustrated in FIG. 8 (hydraulic stamping of parts). Connected to the device is stamp 97 with space 98 communicating with chamber and space 99 of die 100.

Spaces

98 and 99 are overlapped by valve 101 during the compression stroke of piston 3, and communicate with each other when piston 3 impacts on the liquid of highpressure chamber 5. For the purpose of stamping, blank 102 is placed on die 100.

If the volume of the article to be stamped is less than the volume of the liquid discharged during one stroke of piston 3 blank 102 is stamped during one discharge of the spray.

If otherwise, the number of discharges is determined by the volume, and strength of the material of the blank to be stamped. The maximum volume of the blank to be stamped is determined by the required pressure and compression ability of the stamping liquid. If a nonreturn valve is employed (not shown in the drawing) and if leakage from space 98 is eliminated, the volume of this space can be increased unlimitedly.

FIG. 9 illustrates a special case, when the device is employed as a press. The liquid being discharged from the high-pressure chamber through opening [6] 6 affects piston 103 of the press, thus moving it. Piston 103 carries the working member 104. Touching the blank, piston 103 treats the latter. In the above-described case the device may perform cold volume stamping, press welding, embossing, pressing, etc.

As compared with the commonly-used hydraulic presses the speed of piston 103 is much higher, thus providing for the possibility of plastic press deformation of such materials as copper, brass, steel, aluminum. Under the same condition the press in this embodiment has significantly smaller overall dimensions, than usual hydraulic and mechanical presses. As compared with the mechanical presses, the press in this embodiment can withstand overloading, as the maximum possible load is determined not by the amount of energy receiving during one working stroke, but by the maximum liquid pressure. Efforts in this case are received by rigid links 105.

Due to the pulse character of the process it is possible to use great efforts developed by the press without imparting them to rigid links.

This case is illustrated in FIG. 10 with reference to the embodiment of the device used for crushing rocks. The device employing the same principle can be used for rock excavations.

It is more expedient to use the described device as a hydraulic press, in which the efforts are imparted to through a movable thrust mass. This case is illustrated in FIG. 11.

Thrust mass 106 with die 107 and a device with connected vessel 108 housing piston 109 are installed so that they can move relatively to each other. Treated workpiece 110 is placed between piston 109 carrying the Working member, for instance the punch (conventionally shown in the drawing is the piston only), and movable die 107. Prior to operation, the device and thrust mass 106 are pressed to treated workpiece 110 with the force providing for the return of piston 109 to the initial position. At the moment of the impact of piston 3 upon the liquid, the latter shifts piston 109, which performs useful work and, for instance, punches holes in blank 110. The inertia of thrust mass 106 and of the device in this case serves as a support.

The advantages of this press are: the absence of a solid base as is necessary for a forging hammer, the absence of an operating frame, receiving the forces, such as usually 10 used with hydraulic presses, and independence of the maximum effort value upon the energy liberated during the impact, due to the absorbing action of the liquid.

What is claimed is:

1. A device for building up high pressure pulses of liquid, comprising at least one cylinder and one piston housed in said cylinder; said cylinder having at one side of the piston a first space connected through an opening in the cylinder with at least one receiver filled with compressed gas and serving as a low-pressure chamber; said cylinder hav ing at the other side of the piston a second space in the body of the cylinder face portion, filled up with liquid and provided with at least one outlet opening; said second space having a cross-section corresponding to the crosssection of the piston and serving as a high pressure chamber, said high pressure being built up as a result of the impact of said piston upon the liquid, said piston including in the face portion at the side of the high pressure cham ber a taper-shaped lug; circular grooves being provided on the external surface of the piston portion entering the high-pressure chamber; an angular through channel being provided in said piston and connecting its side surface with the face surface at the side of the low pressure chamber; a non-return valve with a through opening being provided in the plunger of said non-return valve located in said angular channel; said cylinder having in the side Wall of the high pressure chamber at least one opening for delivering the liquid under pressure for forced travel of said piston in the direction of the low-pressure chamber, openings serving for the discharge of the liquid during the piston working stroke; a cylindrical bushing to open and close said openings and having a reciprocating motion along the external surface of said cylinder; jacks secured to the external surface of said cylinder, the rods of said jacks being rigidly connected to the cylindrical bushing with one of the spaces of each jack being connected to a main line delivering the liquid under pressure for travel of the piston, and the other space of each jack communicating with said receiver filled with compressed gas; a command valve including a protruding pin entering the low pressure chamber in the face wall of said cylinder, limiting the low pressure chamber and connecting the hydraulic space of each said jack with the atmosphere with said piston acting upon said protruding pin of said command valve.

2. A device according to claim 1, having a spray head connected to the outlet opening of the high pressure chamber of said device; and a slide valve connected by means of a system of levers and a drive with the rod of one of the jacks of said device and used to periodically open and close the outlet opening in said spray head,

3. A device for building up high pressure pulses of liquid, comprising at least one cylinder and one piston including a rod, housed in said cylinder; said cylinder having at one side of the piston a first space connected through an opening in the cylinder with at least one receiver filled with compressed gas and serving as a low pressure chamber; said cylinder having at the other side of said piston a second space in the body of its face portion and filled with liquid and having at least one outlet opening; said second space having a cross-section corresponding to the cross-section of the rod and serving as a high pressure chamber, said high pressure resulting from impact of the rod of said piston upon the liquid, said highpressure chamber having at the side of said piston a widening providing for free entry of the rod into the chamber; said cylinder having in its body at the point of the location of said Widening channels connecting the high pressure chamber with the space in front of said piston; said rod including a taper-shaped lug, circular grooves being provided on the rod in that portion entering the high-pressure chamber; an angular through channel being provided in said piston, connecting the side surface thereof with the surface facing the low-pressure chamber; a non-return valve including a plunger and having a through opening in the plunger, said non-return valve being located in said angular channel to permit flow from the low-pressure hamber; said cylinder being provided adjacent the highressure chamber with at least one opening for delivering quid under pressure for forced travel of said piston in 1e direction of the low pressure chamber; openings being rovided in the cylinder for the discharge of the liquid uring the working stroke of the piston; a cylindrical ushing for closing and opening said openings and adapted or reciprocating motion along the external surface of said ylinder; jacks secured to the external surface of said ylinder and including rods rigidly connected to said cylinrical bushing, with one of the space of each jack being onnected to a main line delivering liquid under pressure )1 travel of the piston, and the other space being conected to said receiver filled with compressed gas; a comiand valve on said cylinder including a protruding pin ntering the low-pressure chamber for limiting the loW- ressure chamber and connecting the hydraulic space of ach said jack with the atmosphere, with said piston acting pon said protruding pin of said command valve.

4. A device for building up high pressure pulses of lquid, comprising at least one cylinder and one piston .oused in said cylinder; said cylinder having at one side of he piston a space connected through an opening in the ylinder with at least one receiver filled with compressed as and serving as a low pressure chamber; said cylinder icluding an internal lug at the other side of said piston; aid piston having at the side of said lug a space filled with iquid and serving as a high pressure chamber, said high Iressure being built up as a result of the impact of the pison upon the liquid, said lug of said cylinder entering the pace of said piston, said space having a cross-section coresponding to the cross-section of said lug; said lug having n the portion entering the high presure chamber circular rooves; said space in said piston having a widening proiding for free entry of said lug into the latter said space; aid piston having adjacent said widening, channels con- ,ecting the high pressure chamber with the space in said iston, a taper-shaped lug in said high pressure chamber; n angular through channel provided in said piston and onnecting its side surface with the surface facing the lowressure chamber; a non-return valve including a plunger nd provided with a through opening in the plunger, said .on-return valve being located in said angular channel; aid cylinder including a side Wall adjacent the high-presure chamber provided with at least one opening for delivring liquid under pressure for forced travel of said piston n the direction of the low pressure chamber, said cylinder eing provided with openings for the discharge of liquid .uring the piston working stroke; a cylindrical bushing to lose and open said openings and adapted for reciprocat- 1g motion along said cylinder; jacks secured to said cylin- .er and including rods rigidly connected to said cylindrical ushing, with one of the spaces of each jack being con- ,ected to a main line delivering liquid under pressure for ffecting travel of the piston, and the other communicatng with said receiver filled with compressed gas; a comland valve on said cylinder including a protruding pin ntering the low pressure chamber for limiting the low iressure chamber and connecting the hydraulic space of ach said jack with the atmosphere with the said piston cting upon the protruding pin of said command valve.

5. A device for building up high pressure pulses of iquid, comprising at least one cylinder and one piston .oused in said cylinder; said cylinder having at one side f the piston a first space connected through openings lith a plurality of receivers located around said cylinder nd filled with compressed gas and serving as a low presure chamber; said cylinder having at the other side of the iston a second space filled with liquid and provided with t least one outlet opening; said second space having. a ross-section corresponding to the cross-section of the |iston and serving as a high pressure chamber, said high Iressure being built up as a result of the impact of said liston upon the liquid, said piston including at the side if the high pressure chamber a taper-shaped lug; circular grooves provided on the piston portion entering the high pressure chamber; an angular through channel being provided in said piston and connecting its side surface with the surface facing the low-pressure chamber; a non-return valve including a plunger with a through opening, said non-return valve located in said angular channel and permitting flow from the low-pressure chamber; said cylinder having adjacent the high-pressure chamber at least one opening for delivering liquid under pressure for the forced travel of said piston in the direction of the low pressure chamber, openings being provided in the cylinder for the discharge of liquid during the piston working stroke; a cylindrical bushing for closing and opening said openings and adapted for reciprocating motion along the external surface of said cylinder; jacks on said cylinder and including rods rigidly connected to said cylindrical bushing, one of the spaces of each jack being connected to a main line delivering liquid under pressure for effecting travel of the piston, and the other space of each jack communicating With at least one of said receivers filled with compressed gas; a command valve on said cylinder and including a protruding pin entering the low pressure chamber for limiting the low pressure chamber and connecting the hydraulic space of each said jack with the atmosphere, with said piston acting upon said protruding pin of said command valve.

6. A device for building up high pressure pulses of liquid, comprising at least one cylinder and one piston including a rod, housed in said cylinder; said cylinder having at one side of the piston a first space connected through openings with a receiver located around said cylinder and filled with compressed gas and serving as a low pressure chamber; said cylinder having at the other side of the piston a second space filled with liquid and having at least one outlet opening; said second space having a cross-section corresponding to the cross-section of the rod and serving as a high-pressure chamber, said high pressure being built up as a result of the impact of said piston rod upon the liquid, said high pressure chamber having a widening providing for 'free entry of the rod into said chamber; said cylinder having, adjacent said widening, channels connecting the high pressure chamber with the space in front of said piston; said rod including adjacent the high pressure chamber a taper-shaped lug, circular grooves being provided on the rod portion entering the high pressure chamber, an angular through channel being provided in said piston and connecting its side surface with the surface facing the low pressure chamber; a non-return valve including a plunger provided with a through opening, said non-return valve being located in said angular channel and permitting flow from the lowpressure chamber; said cylinder having at the side of the high-pressure chamber at least one opening for delivering the liquid under pressure for effecting forced travel of the piston in the direction of the low-pressure chamber, said cylinder being provided with openings for the discharge of the liquid during the piston Working stroke; a cylindrical bushing for closing and opening said openings and adapted for reciprocating motion along the external surface of said cylinder; jacks on said cylinder and including rods rigidly connected to said cylindrical bushing with one of the spaces of each jack being connected to a main line delivering the liquid under pressure for travel of the piston, and the other space of each jack communicating with at least one of said receivers filled with compressed gas; a command valve on said cylinder and including a projecting pin entering the low pressure chamber limiting the low pressure chamber and connecting the hydraulic space of each said jack with the atmosphere, with said piston acting upon said protruding pin of said command valve.

7. A device according to claim 6, having a spray head connected to the outlet opening of the high pressure chamber, a slide valve used to periodically close and open the outlet opening in said spray head, a hydraulic cylin- 13 der and a pneumatic cylinder located at both sides of said valve and used to drive the latter, said hydraulic cylinder being connected in turn with the main line supplying licluid under pressure and the atmosphere, whereas the pneumatic cylinder is connected at least with one receiver filled up with compressed gas.

8. A device according to claim 6 having a floating piston housed in said high pressure chamber and having the cross-section corresponding to the cross-section of the high pressure chamber; said floating piston having circular grooves provided on the external surface thereof.

9. A device according to claim 6 having a closed vessel connected to the outlet opening of the high pressure chamber of said device.

10. A device according to claim 6 having a closed vessel connected to the outlet opening of the high pressure chamber of said device through a non-return valve.

11. A device according to claim 6, comprising a die with a blank, placed into said closed vessel in order to stamp a part.

12. A device according to claim 6 having a vessel connected to the outlet opening of the high pressure chamber of said device, a piston housed in said vessel to perform its working stroke under the action of the pressure of the discharged liquid spray, and a working member rigidly connected to said piston housed in said vessel.

13. A device according to claim 6 having a vessel connected to the outlet opening of the high pressure chamber of said device, a piston housed in said vessel and performing its working stroke under the action of the pressure of the discharged liquid spray, a working member made as a punch and rigidly connected to said piston housed in said vessel, and a die mounted on a stationary support to permit treatment of parts by means of said punch.

14. A device according to claim 6 having a vessel connected to the outlet opening of the high pressure chamber of said device, a piston housed in said vessel and performing its working stroke under the action of the pressure of the discharged liquid spray, a working member made as a punch and rigidly connected to said piston housed in said vessel, and a die mounted on a movable support to permit treatment of parts by means of said punch.

15. A device/for building up high pulse pressures of liquid comprising a first cylinder [(1)] (1') (see FIG. 2);

a first piston [(3)] (3) provided with a space (52) and a rod [(9)] (9'), housed in said first cylinder [(1)] (1) and dividing the same into two spaces 1 said rod being provided with circular grooves [(46)] (46) in the outer surface thereof;

said rod further including an end portion;

a taper-shaped lug [(44)] (44') on the end portion of said rod [(9)] (9);

at lesat one receiver [(19)] (19), with compressed gas therein, connected through openings (20') provided in said first cylinder [(1)] (1 to one of said two spaces [(2)] (2'), and forming together with the latter a low-pressure chamber;

a high-pressure cylinder [(4)] (4') coaxially connected to said space (111) and including a front provided with an internal thread [(7)] (7) adapted for being connected to an energy consumer;

said first cylinder including a face wall [(26)] (26); a power cylinder (48) coaxially connected to the face wall [(26)] (26) of said first cylinder [(1)] a compressed gas source (81);

a seecond piston (56) housed in said power cylinder (48) and dividing the same into a space (62) and a space [(118)] (62'), the latter being coupled with a compressed gas source (81), the pressure in which is lower than that in said receiver [(19)] said power cylinder (48) being provided with channels 14 (70) for draining liquid into the atmosphere when the working stroke of said second piston (56) is completed;

said second piston (56) including a hollow rod (54) provided with a channel (59) passing through said face wall [(26)] (26) of said first cylinder [(1)] (1') into said space [(2)] (2') of said first cylinder a source of liquid pressure;

said second piston (56) being provided with channels (121) to supply liquid, when said piston (56) is in its extreme front position, to the channel (59) of said hollow rod (54) from said source of liquid pressure;

earns (58) adapted to engage said first piston [(3)] said power cylinder (48) being provided with channels (71) for supplying liquid into the channel (59) of saidhollow rod (54) and one of said spaces (62-) of said second piston (56) to provide for an engagement of said cams (58) with said first piston [(3)] (3') and the reversal stroke of said second piston said cams (58) being located at the end portion of said hollow rod (54) for engaging said first piston [(3)] (3') of said first cylinder [(1)] (1) under the action of the pressurized liquid supplied via the channel (59) of said hollow rod (54), and releasing said first piston [(3)] (3) from the effect of the compressed gas pressure, supplied through channels "(64), circular groove (65) and annular slot (63) provided in said first piston [(3)] (3');

a first non-return valve (68) fixed in said face wall [(26)] (26'), and connecting said one s ace [(2)] (2') of said first cylinder [(1)] (1') to the compressed gas receiver (19') [(19)] after the openings [(20)] (20) of said first cylinder [(1)] (1) are closed by said first piston [(3)] (3) during the reversal stroke thereof;

a [control] command valve [(30)] (30) including a membrane (119);

a second non-return valve (69) fixed in said face wall [(26)] (26) of said first cylinder (1') [(1)], and connecting one said space [(2)] (2) of said first cylinder [(1)] (1) to the [control] command valve [(30)] (30), when said first piston [(3)] (3') acts upon said command valve [(30)] (30) at the end of its reversal stroke;

a [second] control valve (76);

said [control] command valve [(30)] (30) being connected through opening (79) to said source of liquid pressure, said second non-return valve (69), said [second] control valve (76), and the atmosphere, and opened by the compressed gas acting upon said [membrance] membrane (119) of the command valve [(30)] (30') when said first piston [(3')] (3') operates said second non-return valve said [second] control valve (76) being constantly connected to said compressed gas receiver (19), [the first] said [control] command valve [(30)] (30'). one of said spaces (62) of said power cylinder (48) and connected to the atmosphere at the end of the working stroke of said second piston ('56);

and a high-pressure chamber [(5)] (5') in sait high-pressure cylinder [(4)] (4), provided with 2 channel (49) for supplying liquid therein, the cross section of said chamber corresponding to the cross section of said rod [(9)] (9) of said first pistor there being provided at least one outlet opening [(6)] (6) in said high-pressure chamber 5)] (5'), f0] draining from the device liquid under a high pressure built up as a result of an impact received frorr said [first piston] first piston [(3)] (3) acceleratec' to high speed by the compressed gas in the low-pressure chamber.

16. A device for building up high pressure pulses of quid comprising: a rigid member having an elongated losed end bore therein; a piston axially movable within aid bore to form axially variable chambers therein; zid piston moving cyclically through an initial half cycle rroke from adjacent one end of said bore to adjacent 2e other end thereof and through a return half cycle froke in a reverse manner; gas containing means in as flow communication through a major portion of each f said strokes with one of said chambers formed in part y said other end of said bore; said rigid member having quid inlet means in constant communication with the ther of said chambers which is adapted to be connected 7 a source of liquid under pressure; said rigid member aving liquid outlet means communicating with said other hamber during a major portion of each of said strokes; alve means cooperable with said liquid outlet means 7 selectively control the opening and closing of said quid outlet means; valve actuating means cooperable ith said valve means and operable in: timed relationship ith the movement of said piston to open said liquid utlet means at the end of said initial stroke and maintain aid liquid outlet means open during said return stroke nd to maintain said liquid outlet means closed during aid initial stroke; said rigid member having impact hamber means extending from said one end of said ore; said piston having impact means extending thereomand towards said one end of said bore; and said npact means being slidably received in said impact chamer means in substantially liquid tight relationshp thereth throughout the movement of said piston during the titer portion of said return stroke.

17. A device as specified in claim 16 wherein said npact means is cylindrical and coaxial with said piston nd said impact chamber.

18. A device for building up high pressure pulses of quid as specified in claim 16 additionally comprising; assageway means communicating with the portion of tid one chamber adjacent said other end of said bore,- leans cooperable with said passageway means operable r limit the maximum gas pressure in said portion of said ne chamber during the final portion of said initial stroke. 19. A device for building up high pressure pulses of quid as specified in claim 16 additionally comprising; assageway means communicating between said gas coniining means and the portion of said one chamber adjaznt said other end of said bore; means cooperable with lid passageway means to limit the rate of gas flow into tid portion of said one chamber through said passageway teans from said gas receiving means and to allow subantially free flow from said portion of said one chamber 1' said gas receiving means.

20. A device as specified in claim 16 wherein said alve actuating means comprises at least one valve acturing piston connected to said valve means; valve actuatrg cylinder means encompassing said valve actuating iston; said valve actuating cylinder means being in fluid ow communication with said liquid supply means at one 1d portion and in fluid flow communication with said as containing means at the other end portion of said ilve actuating cylinder means.

21. A device as specified in claim 16 wherein said iston blocks liquid flow through said liquid outlet means uring the final portion of said return stroke.

22. A device for building up high pressure pulses of quid comprising; at least one cylinder and one power :ston housed in said cylinder; said power piston forming "st and second reciprocally axially variable chambers ithin said cylinder between first and second head surrces of said power piston and inner surfaces of first and 'cond cylinder head means respectively; said first chamer having at least one gas flow port through the wall of rid cylinder at the point axially spaced from said inner surface of'said first cylinder head means; gas receiving means connected to said gas flow port by free flow fluid conducting means; said second chamber having at least one liquid inlet port through said wall inwardly adjacent said second cylinder head means; said second chamber having at least one liquid outlet part through said wall at a point axially spaced from said second cylinder head means; said liquid inlet ports adapted to be connected to a pressurized liquid supply; outlet valve means for opening and closing said liquid outlet ports; valve actuating means for operating said outlet valve means operable to open said outlet valve upon near approach of said power piston to said first cylinder head means; impact chamber means extending axially from said inner surface of said second cylinder head means; impact piston means extending from said second head surface of said power piston coatxially with said impact chamber means; said impact piston means being dimensioned and provided with seal means to be slidably received in said impact chamber in substantially liquid tight relationship therewith; passageway means communicating between said gas receiving means and the portion of said first chamber adjacent said inner surface of said first cylinder head means; valve means cooperable with said passageway means to limit the rate of gas flow through said passageway means into said last mentioned portion of said first chamber from said gas receiving means and to allow substantially free flow from said chamber portion to said gas receiving means.

23. A device as specified in claim 22 wherein said outlet valve means is a hollow cylindrical valve surrounding said cylinder and is axially movable to open and close said outlet ports.

24. A device as specified in claim 23 wherein said hollow cylindrical valve is actuated by valve actuating piston means connected to said valve and movable in a valve actuating cylinder in response to pressure difierential between end portions of said cylinder; one end portion of said valve actuating cylinder being in fluid flow communicating with said gas receiving means and the other end portion of said valve actuating cylinder adapted to be in vented fluid flow communication with sucha liquid supply means.

25. A device as specified in claim 24 wherein there is a liquid venting command valve means in a conduit adapted to provide said fluid fiow communicating between such a liquid supply means and said other end portion of said valve actuating cylinder; said command valve means having actuating means operable by said power piston to vent said conduit and provide for gas powered movement of said valve actuating piston to open said outlet valve.

26. A device as specified in claim 25 wherein said liquid venting command valve means in said conduit comprises; a command valve; an actuating rod in said command valve means extending from. within said command valve means into said first chamber and into the path of said power piston near the end of stroke of said piston to open said command valve when struck by said power piston; said command value means being designed to hold said command valve open as long as liquid from said valve actuating cylinder means is in venting flow therethrough and means within said command valve means to close said command valve at the end of said last mentioned venting flow.

27. A device as specified in claim 22 wherein said impact piston has a smaller diameter tapered coaxial extension portion extending away from said power piston.

28. A device as specified in claim 22 wherein said impact chamber is a generally cylindrical bore extending within said second cylinder head means with a tapered countersink portion adjacent the interior surface of said second cylinder head means.

29. A device as specified in claim 28 wherein a plurality of liquid conducting passageways extends from adjacent the transition area where said countersink portion joins said cylindrical chamber surface to points on said inner surface of said second cylinder head means.

30. A device for building up high pressure pulses of liquid comprising: a rigid member having an elongated closed end bore therein; a wall member transversely dividing said bore into two cylinder portions; a double headed piston axially movable within said bore to form two pairs of axially variable chambers therein by cooperation of each piston head with a respective cylinder portion; said piston moving cyclically through an initial half cycle stroke from adjacent one end of said bore to adjacent the other end thereof and through a return half cycle stroke in a reverse manner; gas containing means in gas flow communication throughout a major portion of each of said strokes with one of said chambers formed in part by said wall member; said rigid member having liquid inlet means in constant communication with the other of said chambers formed in part by said wall member and adapted to be connected to a source of pressurized liquid; said rigid member having liquid outlet means constantly communicating with said other chamber; valve means carried by said rigid member and selectively operable to control the opening and closing of said liquid outlet means; valve actuating means carried by said rigid member operative in timed relationship with the movement of said piston to open said liquid outlet means at the end of said initial stroke and maintain said liquid outlet means open during said return stroke and to maintain said liquid outlet means closed during said initial stroke; said rigid member having impact chamber means extending from said one end of said bore; said piston having impact means extending therefrom and towards said one end of said bore; said impact means being slidably received in said impact chamber means in substantially liquid tight relationship therewith throughout the movement of said piston during the latter portion of said return stroke; liquid inlet means connected tosaid impact chamber; and flow control means in said inlet means to prevent outflow of liquid therethrough.

31. A device for building up high pressure pulses of liquid as specified in claim 30 wherein said two piston heads are connected by a smaller diameter rod member rigidly secured to one of said piston heads and releasably attached to the other of said piston heads by latching means.

32. A device for building up high pressure pulses of liquid as specified in claim 31 wherein said latching means is operable by pressurized liquid to efiect said attachment of said other piston head to said rod member and operdirection; thereafter impacting said movable member I upon a hydraulic fluid contained within a chamber having a restricted movement of liquid therefrom and the volume of which is decreased by movement of said movable member during the latter portion of said movement in said opposite direction.

34. A method for producing high pressure pulses 0 liquid as specified in claim 33 including the further steps of resupplying said chamber with said liquid and repeating all subsequent steps in a prolonged series of identical rapidly repeated cycles.

35. A method as defined in claim 33 in which said converting commences immediately upon cessation 0 said compressing.

36. A method as defined in claim 35 in which said hydraulic force is produced by constantly supplying a liquid under pressure to a liquid contacting face of said movable member.

References Cited The following references, cited by the Examiner, are of record in the patented file of this patent or the original patent.

UNITED STATES PATENTS 1,389,300 8/1921 Gasche -545 2,357,632 9/ 1944 Cornelius 6054.5

2,787,123 4/1957 Delvaux 6057 2,827,764 3/1958 Simmonds 60-51 3,191,383 6/1965 Basset 60-545- 2,540,347 2/ 1 Pounds 60-57 2,032,185 2/ 1936 Sciaky.

2,789,510 4/1957 Meynig 417402 MARTIN P. SCHWAD'RON, Primary Examiner A. M. ZUPCIC, Assistant Examiner US. Cl. X.R.